不同品种鸽蛋组分、蛋白透明度差异比较及相关性分析

为探究造成鸽蛋蛋白出现透明度差异的原因,对不同品种鸽蛋组分、鸽蛋蛋白透明度差异及两者间的相关性进行了分析研究。结果显示:①不同品种间鸽蛋的蛋黄、蛋白和蛋壳组分差异不显著(P0.05),不同品种间的鸽蛋蛋白透明度差异不显著(P0.05),但白羽王鸽鸽蛋蛋白透明度存在低于其它4个品种鸽趋势(P0.10);②不同透明度的鸽蛋,其组分间重量和比例差异极显著,透明鸽蛋的蛋重、去壳蛋重、蛋白重和比例均极显著低于不透明鸽蛋(P0.10);③数据间相关和偏相关分析均显示,鸽蛋白透明度测定值(明度值)与蛋白重呈现出极显著的相关关系(R~2=0.28)。研究表明,5个品种间鸽蛋的蛋黄、蛋白和蛋壳组分重和比例均差异不大,但白羽王鸽有凸显出较低蛋白透明度趋势;较小蛋白重和较低蛋白比例的鸽蛋,具较高蛋白透明度;相关和偏相关分析证实,造成鸽蛋蛋白透明度出现变化的根源在于其蛋白组分,而与蛋黄和蛋壳等无关。     

色差计评价鸽蛋蛋白透明度方法的建立

试验旨在建立色差计评价鸽蛋蛋白透明度的方法,为鸽蛋蛋白透明形成机理的研究奠定理论基础,同时也为鸽蛋的市场销售提供一个评价指标。选取180个新鲜非受精白羽王鸽鸽蛋,煮熟后进行感官评分和蛋白明度的测定,并以明度范围来划分鸽蛋蛋白透明度。结果显示:感官评分透明、半透明和不透明鸽蛋所占比例分别为13.45%、41.52%和45.03%;不同透明度组鸽蛋蛋白色差计所测明度呈极显著差异(P0.01);将透明、半透明和不透明的明度范围划分为≤45、45~55、≥55,与感官评分的一致度达到91.23%。综上所述,色差计所测明度可作为衡量鸽蛋透明度的标准,透明、半透明和不透明鸽蛋的明度范围分别为≤45、45~55、≥55。     

不同贮存条件对鸽蛋新鲜度、组分、蛋品质及蛋白透明度的影响

本试验分析了不同贮存温度和时间对鸽蛋新鲜度、组分、蛋品质及蛋白透明度的影响,寻求鸽蛋贮存的最佳条件,并探索不同贮存条件下鸽蛋蛋白透明度的变化规律,为实际生产中鸽蛋合理贮存和出售提供理论依据。以1～2岁公母配对白羽王鸽为试验对象,采用3(低温、中温、高温)×4(1、2、3、4周)因子交叉完全随机设计,试验开始后每周随机采集90枚鸽蛋,分别放置在3种不同温度条件下,每组30枚,分别持续1、2、3、4周,而后对鸽蛋进行新鲜度、组分、蛋品质及蛋白透明度的测定分析。结果显示,低温条件下,鸽蛋放置4周未出现散黄和可见霉变现象。高温和中温条件下,鸽蛋只可放置1周不变质。随着时间的延长和温度的升高,鸽蛋的失重率显著上升(P0.05)。时间对蛋壳率、蛋白率及蛋黄率均有显著影响(P0.05),但温度对其无显著影响(P0.05)。不同贮存温度和时间对鸽蛋的蛋白高度和蛋黄颜色均有显著影响(P0.05),即随着时间的延长和温度的升高,鸽蛋的蛋白高度呈下降趋势,蛋黄颜色变深。不同贮存温度和时间对煮熟的鸽蛋蛋白L~*、a~*和b~*值均有显著影响(P0.05);中温贮存透明鸽蛋所占比例最高。综上所述,鸽蛋贮运和贩售需在冷藏条件下进行。在低温冷藏条件下,鸽蛋可贮存4周以上。在中温条件下(20℃左右)保存,有利于提高鸽蛋蛋白透明度。     

不同贮存条件对鸽蛋新鲜度、组分、蛋品质及蛋白透明度的影响

本试验分析了不同贮存温度和时间对鸽蛋新鲜度、组分、蛋品质及蛋白透明度的影响,寻求鸽蛋贮存的最佳条件,并探索不同贮存条件下鸽蛋蛋白透明度的变化规律,为实际生产中鸽蛋合理贮存和出售提供理论依据。以1~2岁公母配对白羽王鸽为试验对象,采用3（低温、中温、高温）×4（1、2、3、4周）因子交叉完全随机设计,试验开始后每周随机采集90枚鸽蛋,分别放置在3种不同温度条件下,每组30枚,分别持续1、2、3、4周,而后对鸽蛋进行新鲜度、组分、蛋品质及蛋白透明度的测定分析。结果显示,低温条件下,鸽蛋放置4周未出现散黄和可见霉变现象。高温和中温条件下,鸽蛋只可放置1周不变质。随着时间的延长和温度的升高,鸽蛋的失重率显著上升（P<0.05）。时间对蛋壳率、蛋白率及蛋黄率均有显著影响（P<0.05）,但温度对其无显著影响（P>0.05）。不同贮存温度和时间对鸽蛋的蛋白高度和蛋黄颜色均有显著影响（P<0.05）,即随着时间的延长和温度的升高,鸽蛋的蛋白高度呈下降趋势,蛋黄颜色变深。不同贮存温度和时间对煮熟的鸽蛋蛋白L^*、a^*和b^*值均有显著影响（P<0.05）;中温贮存透明鸽蛋所占比例最高。综上所述,鸽蛋贮运和贩售需在冷藏条件下进行。在低温冷藏条件下,鸽蛋可贮存4周以上。在中温条件下（20℃左右）保存,有利于提高鸽蛋蛋白透明度。     

日粮不同粗蛋白水平对白羽王鸽产蛋性能、鸽蛋组分与蛋白透明度的影响

试验旨在研究日粮不同粗蛋白水平对白羽王鸽产蛋性能、鸽蛋组分与蛋白透明度的影响。选取216对双母配对白羽王鸽,随机分为6处理组(每处理组36对、每重复6对),分别采食等能等氨基酸模式下不同粗蛋白水平(4.0%、6.0%、8.0%、10.0%、12.0%、14.0%CP)日粮。预试期1周,正试期16周。结果显示:①日粮不同粗蛋白水平显著影响月产蛋数、料蛋比(P0.05),极显著影响体增重(P0.01),日粮低粗蛋白水平显著减少月产蛋数,增大料蛋比,致体重极显著降低。②日粮不同粗蛋白水平对蛋重、蛋白重、蛋白和蛋黄百分数存在极显著(P0.01)影响,随日粮粗蛋白水平的下降,蛋白重和蛋白比例下降,蛋黄比例极显著地上升。③日粮粗蛋白水平显著(P0.05)影响鸽蛋透明度分型结果,但并未显现出一致性升高或降低的趋势性变化。研究表明,在本试验氨基酸模式下,以月产蛋数、料蛋比和体增重为评价指标,日粮粗蛋白水平可由14%降至10.0%并获得较好产蛋性能;日粮粗蛋白水平主要通过影响蛋白重,进而影响鸽蛋重、蛋黄和蛋白比例;日粮粗蛋白水平显著影响鸽蛋蛋白透明度,但影响鸽蛋蛋白透明度的因素可能不单日粮粗蛋白水平一种。     

肉鸽蛋与鸡蛋生物学特性的比较

试验同时测定肉鸽蛋和鸡收，相互比较，了以解肉鸽蛋的生物特性。鸽蛋重量为鸡蛋的４１．２６％，悼 壳表面积为鸡蛋的５４．１８％，单位面积蛋壳重为鸡蛋的５８．８７％；肉鸽蛋平均重２２．４５±２．２９ｇ，蛋重范围１７．１－２９．６，其蛋白部分蛋总重的７２．３３％，蛋黄和蛋壳分别占２０．８５％和６．８２％；鸽蛋哈氏单位、蛋壳厚度和蛋壳强度低于鸡蛋；鸽蛋的蛋重与蛋壳比例呈极显著负相关，蛋白比例与哈氏单位，蛋黄     

人工孵鸽与孵鸡技术的差别

随着我国规模养鸽业的迅猛发展和人工哺喂乳鸽技术的提高和应用,使人工孵鸽也与日俱增。人工孵化是现代养鸽业增产增收的新技术,许多人认为人工孵鸽与孵鸡相同,然而事实并非如此。由于鸽与鸡在品种生物学特性上的差异,各自对胚胎发育条件要求也不尽相同,主要差异表现在如下方面。一、物种的差异１．鸽蛋与鸡蛋不同：鸽蛋外壳光滑,蛋壳结构坚韧细密,透气性差而蒸发水分慢,酷似番鸭蛋而又有不同;蛋内的蛋白与蛋黄不同,鸡蛋的蛋白占５５．８％。蛋黄占３１．９％、蛋壳占１２．３％,而鸽蛋的蛋白多达７４％、蛋黄只占１７．９％、蛋…     

鸽蛋低密度脂蛋白对冷休克和冻融猪精子HSP70及凋亡相关基因表达的影响

旨在探究鸽蛋低密度脂蛋白(LDL)对冷休克和冻融猪精子HSP70及凋亡相关基因表达的影响。试验分为5组,分别是鲜精组、3%LDL(-80和-196℃)处理组、9%LDL(-80和-196℃)处理组。采用CASA系统分析不同处理组添加不同浓度鸽蛋LDL对冷休克及冻融前后猪精子生物学性状的影响;通过SDS-PAGE、Western blotting、PCR扩增检测分析HSP70蛋白及凋亡基因表达量的变化。结果表明:猪精子经过冻融处理后,热休克蛋白HSP70的表达量高于鲜精组,同时添加9%鸽蛋LDL并置于-196℃保存的冻融精子的热休克蛋白HSP70的表达量与鲜精组无显著差异(P0.05);在抗凋亡基因Bcl-x1、Bcl-2l试验中,鲜精组的基因表达量均高于其他处理组,添加9%LDL(-196℃)处理组的基因表达量与鲜精组无显著差异(P0.05);在促凋亡基因Bak试验中,鲜精组的基因表达量最低,且添加9%LDL(-196℃)处理组的Bak基因表达量与鲜精组无显著差异(P0.05)。添加鸽蛋LDL可在一定程度上降低猪精子在冻融过程中造成的损伤,维持猪精子正常生物学性状,提高猪精子存活率。     

不同培养时间对猪卵母细胞透明带蛋白泛素化及其体外授精的影响

通过热溶解-溶解透明带蛋白、SDS-PAGE检测蛋白和Western blot分析透明带蛋白泛素化水平,探讨不同培养时间(34 h、46 h、58 h)对猪卵母细胞透明带蛋白泛素化表达量的影响。结果表明:培养46 h组猪卵母细胞成熟率显著高于34 h组和58 h组,死亡率显著低于34 h组和58 h组;体外授精过程中,培养46 h组猪卵母细胞的卵裂率、4-细胞、囊胚率均显著高于34 h和58 h组,而34 h和58 h组没有显著性差异;培养46 h组猪卵母细胞透明带蛋白泛素化水平显著高于34 h和58 h组,而34 h和58 h组没有显著性差异。结果提示,不同培养时间对猪卵母细胞透明带蛋白泛素化和体外授精有显著影响。     

鉴别食用植物油质量的方法

鉴别食用植物油质量的主要方法有： （1）观察透明度。质量好的植物油透明度高,水分、杂质少。静置24小时以后,清晰透明、不混浊、无沉淀、无悬浮物。反之,则质量差。     

Effects of housing system (outdoor vs cages) and age of laying hens on egg characteristics

1. Effects of two housing systems (cages vs outdoor) on external and internal egg characteristics were investigated. 2. In total 785 eggs from three different lines in cages and 268 eggs from outdoor-housed layers were examined for egg weight, albumen, yolk and shell content, albumen height and pH, and albumen and yolk dry matter content. 3. Interactions between layer age and housing systems were found for egg weight, eggshell content, albumen height, albumen pH, and dry matter content of the albumen and yolk. This was mainly due to the greater variation with age in the outdoor layers, compared to the caged layers. 4. Irrespective of age eggs from outdoor layers were relatively broader than eggs from the caged layers. Yolk colour was considerably darker in the outdoor group (11.0 vs 9.3). 5. We concluded that it is more difficult to maintain constant external and internal egg quality in an outdoor housing system than in a battery cage system. Factors that determine the greater fluctuations in internal egg quality need to be investigated.     

生物保健型蛋白饲料对蛋品质影响的试验研究

选择320日龄海兰褐蛋鸡234只,共分A(对照组)、B、C3个处理组,采用生物保健型蛋白饲料(SBD)代替蛋鸡日粮中的部分豆饼,通过56d的饲喂试验。结果表明:用3%生物保健型蛋白饲料代替日粮中3%的豆饼时,平均蛋重、产蛋率、破软蛋率、采食量都与对照组无显著差异(P>0.05);用5%生物保健型蛋白饲料取代饲粮中5%的豆饼时,平均蛋重、破软蛋率、与对照组无显著差异(P>0.05),但产蛋率、采食量与对照组相比均有下降(P>0.01),在蛋的品质方面未产生不良影响,只是C组的蛋黄颜色比A、B组偏黄,铜(Cu)的含量偏高。由此可见采用生物保健型蛋白饲料代替蛋鸡日粮中3%的豆饼,效果最佳。     

Double-yolked pheasant eggs provide an insight into the control of albumen secretion in bird eggs

1. The possible role of the presence of the yolk in stimulating secretion of albumen was investigated. 2. Double-yolked and single-yolked pheasant (Phasianus colchinus) eggs were opened to determine the masses of the shell, albumen and yolk(s). 3. In double-yolked eggs, the two yolk masses were not significantly different. Albumen mass was increased above that expected from an egg with a single-yolk of comparable size but below that expected from an egg having a mass of the combined yolks. The mass of shell per unit area reflected the mass of the initial mass of the egg irrespective of the number of yolks. 4. The additional mass of albumen is unrelated to yolk or initial egg mass. It is postulated that in double-yolked eggs the oviduct is mechanically stimulated by the presence of both yolks, which empties the stores of water-soluble albumen proteins in the magnum wall. Such stores are insufficient to provide the same amount of protein for the two yolks.     

Bacteriologic findings in ostrich (Struthio camelus) eggs from farms with reproductive failures

From January 2001 to December 2002, 543 ostrich eggs were submitted for bacteriologic investigation. The eggs were laid by 387 domesticated ostriches that suffered fertility disorders and that came from 44 farms located in different areas of Northern and Central Italy. Microbiologic investigations showed bacterial isolation in 105 (19.3%) of 543 eggs examined, with a high prevalence of enterobacteria from albumen and yolk. In only a few cases did bacterial isolation result from yolk or albumen alone. An antibiotic sensitivity test was conducted on isolates by the Kirby-Bauer disc diffusion method. This is the first report regarding the microbiologic status of eggs from ostrich farms located in different Italian regions.     

Genetic parameters of the thick-to-thin albumen ratio and egg compositional traits in layer-type chickens

ABSTRACT

1. Generating a robust egg albumen is one of the major factors contributing to interior egg quality owing to its nutritive value and superior appearance. However, the genetic factors regulating the proportion of thick albumen are poorly understood.

2. In this study, 1330 eggs were collected from 450 Rhode Island White layers, aged 40 weeks, to measure egg compositional traits for three successive days. The restricted maximum likelihood method was applied to estimate genetic parameters for the thick-to-thin albumen ratio and other egg compositional traits. A univariate animal model was fitted to calculate heritability for each trait.

3. The heritabilities of egg weight, yolk weight, albumen height, Haugh units, percentages of yolk, thick albumen, thin albumen and the thick-to-thin albumen ratio were 0.32, 0.34, 0.28, 0.47, 0.61, 0.39, 0.31, and 0.45, respectively. The percentage of thick albumen was negatively correlated genetically with all traits, and percentage of thin albumen was negatively correlated genetically with all traits except for Haugh units. The thick-to-thin albumen ratio was positively correlated genetically with egg weight, albumen height and Haugh units, with correlations ranging from 0.21 to 0.54.

4. The results indicated that the percentage of thick albumen and the thick-to-thin albumen ratio were found to be moderately to highly heritable, and selection for the thick-to-thin albumen ratio could be conducive to the improvement of egg albumen quality.     

Importance of albumen content in whole-body protein synthesis of the chicken embryo during incubation.

The importance of egg albumen content in whole-body protein synthesis was investigated in developing chicken embryos by using lines genetically selected for high and low albumen contents and by removing albumen from eggs before incubation. 2. Whole-body protein synthesis was estimated by injecting L-[15N]-phenylalanine intravenously on day 12 of incubation. 3. Embryos from high albumen eggs had higher whole-body protein synthesis rates than those from low albumen eggs. 4. Whole-body protein synthesis was reduced by the removal of albumen from eggs before incubation. 5. It was concluded that albumen content per se was of crucial importance in regulating whole-body protein synthesis in chicken embryos during incubation.     

Effects of experimental infection of fowl with EDS'76 virus,infectious bronchitis virus and/or fowl adenovirus on laying performance

Following BCI4 (EDS'76) virus infection of brown layer hens at 33 weeks of age, production of normally shelled eggs dropped from 87 per cent to 49 per cent within 3 weeks. The production of soft shelled and shell‐less eggs attained a maximum of 33 per cent 3 weeks after infection (p.i.). Shell quality recovered completely within 5 weeks p.i.

Egg production problems in White Leghorns infected with BCI4 virus were less severe and of shorter duration than in brown layers.

Both in brown layers and in White Leghorns total egg production, mean weight of normally shelled eggs, and internal egg quality were not affected following BCI 4 virus infection at 33 and 28 weeks of age, respectively. Besides shell abnormalities no clinical disease symptoms were observed. Vaccination with a commercial EDS'76 vaccine (Nobivac EDS'76^®) at 17 weeks of age had no adverse effects on laying performance and provoked adequate immunity against challenge at 33 weeks of age. The same observations were made following BCI4 virus infection at 17 weeks of age.

After infectious bronchitis virus (IBV) (H52 virus) infection of laying fowl the percentage of eggs with shell aberrations (rough, misshapen and/ or soft shells) increased to a maximum of 8 per cent, total egg production was depressed, mean egg weight was reduced I to 2 grams, and up to 10 Per cent of normally shelled eggs showed watery, not ropy thin albumen. This abnormally thin albumen was observed in a considerably higher proportion of eggs with shell defects than in normally shelled eggs. No turbidity of the thick albumen was observed and no symptoms of respiratory disease were noticed.

The severity and duration of adverse effects of IBV infection on laying performance depend very much on the stage of production in which the infection occurs. Following IBV infection at the onset of production a much severer drop in total production and in production of normally shelled eggs, a greater increase in the number of abnormally shelled eggs, and more lasting adverse effects on egg weight and internal egg quality were observed, in comparison with infection after peak production. Compared with single infections, a combined BC14 virus and IBV infection of brown layers at 33 weeks of age resulted in greatly potentiated adverse effects on total egg production, number of eggs with aberrant internal quality, and duration of production problems.

Following a combined BC14 virus and IBV infection, in a great proportion of eggs with shell defects and watery thin albumen, turbidity of the thick albumen was observed also, probably due to combined effects on the uterus of both IBV and BC14 virus.

BC14 virus infection did not reinforce the adverse influence of IBV infection on egg weight.

The same observations as described for the combined BC14 virus and IBV infection were made following BC14 virus infection of fowl previously infected with IBV.

It is concluded that changes of internal egg quality in field cases of EDS'76 are most likely due to subclinical IBV infections.

After infection of brown layers at 33 weeks of age with fowl adenovirus 66 (FA V 66) neither symptoms of clinical disease were observed nor effects on egg production, egg weight, and egg quality. Also, in a combined infection with FA V66, IBV, and BCI4 virus, no pathogenic significance could be attributed to the FAV.     

种鸡场鸡白血病净化的研究(Ⅲ)-ALV检测不同样品种鸡场净化效果的比较

应用双抗体夹心酶联免疫吸附试验 (DAS- EL ISA)在种鸡白血病的净化中 ,针对同一种鸡群 ,同时采用蛋清和肛拭作为试验材料 ,实验反映的结果不同 ;将产第一枚蛋为阳性的鸡隔离饲养 ,检测其以后蛋中 AL V的状况 ,结果发现 :在随后的 2 5天左右的每一枚蛋清中都能检测到 AL V:在不同种鸡场分别采用蛋清、蛋清和肛拭同时作试验样品进行净化 ,跟踪结果发现 :在不同种鸡场中 ,AL V阳性感染率都有不同幅度的下降。另一方面 ,检测雏鸡的胎粪 ,淘汰阳性者 ,到其产蛋期抽检蛋清 ,该群鸡 AL V阳性率有所下降     

不同周龄母鸡鸡蛋及不同蛋壳质地鸡蛋的蛋品质比较

本文比较了同一品种不同周龄(26、40周龄和64周龄)母鸡所产蛋的蛋壳品质和蛋品质,包括蛋重、蛋壳相对重、蛋形指数、蛋壳强度、蛋壳厚度、蛋黄颜色、蛋黄指数、蛋黄比率、哈氏单位、蛋清pH值。之后,还比较了该鸡种不同蛋壳质地鸡蛋(正常蛋和砂壳蛋)之间上述指标的差异。结果表明:在不同周龄母鸡所产蛋之间,蛋重、蛋黄指数、蛋黄比率、哈氏单位等均存在显著差异(p<0.05),而蛋壳厚度之间差异不显著(p>0.05)。此外,蛋重、蛋形指数、蛋黄颜色、蛋黄比率随着母鸡周龄的增加呈上升趋势,而蛋壳强度、蛋壳相对重、哈氏单位、蛋黄指数、蛋清pH值呈下降趋势。最后,蛋壳质地不同的鸡蛋(正常蛋与砂壳蛋)之间,蛋重、蛋壳相对重、蛋壳强度、蛋清pH值之间存在极显著差异(p<0.01),而其他参数之间差异不显著(p>0.05)。